The ambitious program announced Thursday escalates Google’s technological arms race with rival Amazon.com Inc., which also is experimenting with self-flying vehicles to carry merchandise bought by customers of its online store.

Amazon is mounting its own challenges to Google in online video, digital advertising and mobile computing in a battle that also involves Apple Inc.

Although Google expects it to take several more years before its fleet of drones is fully operational, the company says test flights in Australia delivered a first aid kit, candy bars, dog treats and water to two farmers after travelling a distance of roughly one kilometre, or just over a half mile, two weeks ago.

Besides perfecting their aerial technology, Google and Amazon still need to gain government approval to fly commercial drones in many countries, including the U.S. Amazon last month asked the Federal Aviation Administration for permission to expand its drone testing. The FAA currently allows hobbyists and model aircraft makers to fly drones, but commercial use is mostly banned.

Google says it is striving to improve society through the X’s lab’s research, but the Glass device has faced criticism from privacy watchdogs leery of the product’s ability to secretly record video and take pictures. Investors also have periodically expressed frustration with the amount of money that Google has been pouring into the X lab without any guarantee the products will ever pay off.

A team led by Massachusetts Institute of Technology aeronautics professor Nick Roy already has been working on Project Wing for two years, according to Google. The Mountain View, California, company didn’t disclose how much the project has cost.

Drones clearly could help Google expand an existing service that delivers goods purchased online on the day that they were ordered. Google so far is offering the same-day delivery service by automobiles in parts of the San Francisco Bay Area, Los Angeles and New York.

“Self-flying vehicles could open up entirely new approaches to moving goods, including options that are cheaper, faster, less wasteful and more environmentally sensitive than what’s possible today,” Google said in a pamphlet outlining Project Wing.

Google, though, seems to see its drones as something more than another step in e-commerce delivery. The aerial vehicles also could make it easier for people to share certain items, such as a power drill, that they may only need periodically and carry emergency supplies to areas damaged by earthquakes, hurricanes and other natural catastrophes, according to Google’s Project Wing pamphlet.